Hello there ... my 2 cents ... i don't know anything about JACK, but: Main issue here is that gtk is not thread safe (neither is any gui). You should not call anything from another thread that uses the GUI (althoug gdk_thread_eneter/leave seems to be right for it). Maybe replacing the enter/leave code by a call to g_idle_add or g_main_context_invoke. By the way, i think the Gtk folks should keep the API stable and not remove anything until 4.0. People ported applications to gtk 3.0 and then ... it does not work with 3.8. I don't know if QT is different, but this should not be happening. A work around should have been implemented to stay with gdk_threads_enter/leave. cheers, Luis Matos Sáb, 2013-10-19 às 10:24 -0400, Paul Davis escreveu: > > > > On Sat, Oct 19, 2013 at 7:46 AM, Craig Bakalian > <craigbakalian@xxxxxxxxxxx> wrote: > On 10/19/2013 07:11 AM, Paul Davis wrote: > There are dozens if not hundreds of "examples" of this > - any JACK client with a GUI. > > But to get an idea of the basic idea, take a look in > the JACK example clients and/or tools. jack_capture > would be a good place to start, since it faces the > problem of handing over incoming (audio) data to > another thread. > > And no, you are not writing "the data" to a pipe from > the JACK callback. The key ideas are (a) to move the > data to another thread you need to use a lock-free > data structure (b) if you need to wake the other > thread (i.e. because it doesn't simply wake up > periodically and use whatever new data you've > delivered), you need to use the *most* RT-safe method > you can. There are no absolutely RT-safe methods. A > semaphore (on Linux anyway) is the best, writing a > byte to a pipe is the 2nd best. > > You cannot make calls from the JACK callback that may > block - you cannot write to disk, read from disk, take > locks, etc, etc. > > This really should not be going to the gtk-list > anymore. It has roughly nothing to do with gtk and > more or less everything to do with JACK. > > > > Hi Paul, > > If it has nothing to do with JACK, then why on earth was it > working before the latest release of gtk in ubuntu 13.10? Why > could I write data out from the JACK callback with no issues > before?? It has nothing to do with the JACK callback and > everything to do with the overly secure removal of > > gdk_threads_enter(); > gdk_thread_leave(); > > > You are not *allowed* to call these functions from a JACK callback, > whether they exist or not. > > > > My application was working perfectly until the removal of > these functions. Furthermore, once I remove the insert to the > gtktextbuffer from the callback, all is well. And, the error > that pops up is that the gtktextbuffer layout can't get a line > number. This has nothing to do with JACK and everything to do > with threads in gtk. > > > You are not allowed to interact with the GUI toolkit from the > callback. > > > If you use JACK you are doing realtime programming. I suggest a > careful read of this to get you started: > http://www.rossbencina.com/code/real-time-audio-programming-101-time-waits-for-nothing > > > The fact that you are handling MIDI and not audio doesn't change the > applicability of Ross' advice. > > > > What on earth should I expect anything more than "get this off > this list" from I guy whose first response on a HELP list is > "Your design is wrong". It is obvious to me you don't know > what my JACK callback is doing. > > > Maybe you don't understand that I wrote JACK. I run the JACK mailing > list. That is where your questions belong. I'm just trying to be nice > to the poor souls who wonder what this all has to do with GTK. And > btw, moving to Qt won't address any of your fundamental issues. > > --p > > > > > > _______________________________________________ > gtk-list mailing list > gtk-list@xxxxxxxxx > https://mail.gnome.org/mailman/listinfo/gtk-list _______________________________________________ gtk-list mailing list gtk-list@xxxxxxxxx https://mail.gnome.org/mailman/listinfo/gtk-list
